Anthraflavin disulfonic acid and process of making same.



thraflavin Thereoimf which the following is a specifica- -sulfonatinganthrequinon or other organic UNITED sTA Es' PATENT OFFICE.

MICHAEL JLJINSKY, OF CREFELD. GERMANY, ASSIGNOR TO-R. WEDEKIND 6% 00., OF UERDINGEN, GERMANY.

ANTHRAFLAVIN DISULFONIC ACID AND PRGCESS OF MAKING SAME.

No, 826, 510. Original g nman filed July 14, was, also re To all whom it may c0ncern.-

Be it known that I, MICHAEL JLJmsKY, chemist; a. subject of the Russian Emperor, and a resident of Sudstrasse 7 Crefeld, in the German Empire, have invented a new An- Disulfonic Acid and Production tion. In my application, Serial No. 165,426, filed July 14, 1903, I have. described a process of combinations, especially anthracene derive-r tives, in the presence of mercury, (as such or in a combined state) by which process the sulfo group or groups enter in other positions than by the sulfonating process by means of sulfuric acid only. I have found that by this process a new snth'raflavin disulfonic acid is obtained by treating anthrafiavin acid with sulfuric acid in the presence of mercury, as may be illustrated by the following example? one hundred parts of anthraflavin acid, ten parts of mercury, five hundred parts of fuming sulfuric acid of forty per cent. free SO" are slowly brought up to about 120 centigrade. The entire anthraflavin acid is then transferred into a form soluble in water. The sulfonic acid obtained forrns asodium salt easily soluble in sodium lye in excess. This peculiar quality differentiates it sharply from the anthrafiavin sulfonic acid formed without addition of mercury, the sodium salt of. which is insoluble in an excess of sodium lye.

Thejnew acid forms a potassium salt substantially different from the potassium salt of the known anthrafiavin sulfonic salt, as may be seen from the following table:

Specification of Letters Patent.

185,456. Divided and this application filed November 18,1904. Serial He. 283.35?-

on anthraflsvin acid with resence of mercury, substan- Patented July 17, 1908.

Salt of known acid. Salt of new acid.

0.5 gram is in thirty cubic centimeters water, even in the heat, only slightlv soluble.

'Greenlsh-yellow 'solutlon, ery slight intensity.

0 5 gram is soluble in thirty cubic centimeters hot water with red color without residue.

Deep red-brown 501B Solubility in water.

Behavior of the watery eolu- I tion with sulfate a! copper. I

Qyeings: The behavior with copper sulfate is very characteristic and finds its explanar tionhy the different affinity of the two sulfonic acids for onid of copper. The new sulfonic acid forms a far more durable copper lac than the known acid. The new sulfonic acid or its salt is to be used as dyestufl or as material for producing other dyestuffs.

I claim as my invention 1. The new anthrafiavin disulfon-ic acidoharacterized by having the sulfonio grou s in a new position and giving a potassium so. is which forms a yellow powder of microscopical rectangular prisrm not pointed and is soluble in hot water with red color and whose 'wate'ry solution gives with copper sulfate 9.

deep red-brown solution.

2. Process of producing the new anthrafiavin disulfonic acid, consisting in reacting fuming sulfuric acid, in the tially as and or the purpose set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MICHAEL JLJINSKY.

Witnesses W. BRUCE WALLACE, 7 MARGARET WALLACE. 

